This application is related and claims priority under 35 U.S.C. xc2xa7 119 to Japanese Patent Application Number 2000-257202, filed Aug. 28, 2000, the entire contents of which are incorporated by reference herein.
1. Field of the Invention
The present invention relates to a transferring apparatus for chips in which the chips are transferred above an immovable base while being chucked in receiving concavities formed in a transferring member.
2. Description of the Related Art
Conventionally, with respect to measuring and classifying apparatuses in which electrical characteristics of chip-type electronic components are measured and non-defective articles are selected therefrom, an apparatus configured as shown in FIGS. 8 to 11b is known. This measuring and classifying apparatus is constructed such that a turntable 51, which serves as a transferring member, is rotatably disposed on an upper surface 50a of an immovable base 50. The turntable 51 is provided with receiving concavities 51a for receiving chips 52 at the periphery thereof.
In the measuring and classifying apparatus of FIGS. 8-11b, the chips 52 are supplied to the receiving concavities 51a at a supply station, and the turntable 51 is turned in a direction shown by the arrow in FIGS. 8 and 9 while the chips 52 are being chucked by a vacuum source. Accordingly, the chips 52 are sequentially transferred to work stations A, B, and C. Predetermined operations, such as measurements, tests, processings, etc., are performed in the work stations A, B, and C, and the chips 52 are then transferred to an output station.
In addition, each of the receiving concavities 51a formed in the turntable 51 is provided with a suction pass 51b, which is connected to the vacuum source, at a lower corner thereof. Thus, the chips 52 are positioned at the lower corners of the receiving concavities 51a while they are being chucked therein.
However, as shown in FIG. 11A, in the above-described conventional measuring and classifying apparatus, electrodes 52a of the chip 52 slide on the upper surface 50a of the immovable base 50 while the chip 52 is being transferred. Thus, scratches may be formed on the electrodes 52a as shown in FIG. 11B, and soldering defects may occur in a mounting process due to the scratches formed on the surfaces of the electrodes 52a. Accordingly, this disadvantage needs to be overcome in order to increase quality reliability.
In view of the above-described situation, an object of the present invention is to provide a transferring apparatus for chips with which the scratches can be avoided while the chips are being transferred and mounting defects are thereby prevented.
According to the present invention, a transferring apparatus for chips includes an immovable base and a transferring member which is moveably disposed on the immovable base, and which is provided with receiving concavities for receiving the chips and vacuum suction passes for chucking the chips. The chips are transferred above the immovable base while being chucked in the receiving concavities, and the chips are chucked inside the receiving concavities at the other side relative to the immovable base.
The chips may be chucked in such a manner that gaps are provided between the chips and the immovable base.
In addition, compressed air outlets for expelling the chips may be formed in the receiving concavities.
In addition, the upper sides of the receiving concavities formed in the transferring member may be covered by an upper plate, and a low-friction sheet may be disposed between the upper plate and the chips.
In addition, the upper plate may be formed of an elastic body which absorbs an impact force applied to the chips from below.
Accordingly, since the chips are chucked inside the receiving concavities at the other side relative to the immovable base, the chips are transferred while being lifted above the immovable base. Thus, the chips can be prevented from sliding on the immovable base and scratches can be prevented from forming on the electrodes. Therefore, soldering defects in a mounting process can be prevented, and the quality reliability can be increased.
In addition, when the chips are chucked in such a manner that gaps are provided between the chips and the immovable base, the chips are reliably prevented from sliding on the immovable base. Thus, the quality reliability can further be increased.
In addition, when the compressed air outlets are formed in the receiving concavities, the chips are easily taken out from the receiving concavities.
In addition, when the upper sides of the receiving concavities are covered by the upper plate and a low-friction sheet is disposed between the upper plate and the chips, the chips can smoothly be chucked without being entrapped, etc., and easily and reliably be positioned.
In addition, when the upper plate is formed of an elastic body, the impact force applied to the chips from below can be absorbed, so that the chips do not directly receive the impact force. For example, when probe pins, etc., are projected upward from the immovable base and the electrical characteristics of the chips are measured, the chips are prevented from directly receiving the impact force applied by the probe pins.